Lens driving mechanism

ABSTRACT

A lens driving mechanism is provided for driving a first lens and a second lens to move, wherein light enters the first and second lenses along a light incident direction. The lens driving mechanism includes a first base movably connected to the first lens, a first driving assembly, and a second driving assembly. The first driving assembly has a first magnet and a first coil corresponding thereto for moving the first lens. The second driving assembly has a second magnet and a second coil corresponding thereto for moving the second lens. The first magnet is adjacent to the second magnet, and the polar direction of the first magnet is parallel to the light incident direction.

The present application claims priority of U.S. Provisional ApplicationNo. 62/357,557, filed on Jul. 1, 2016, and China Patent Application No.201710495566.X, filed on Jun. 26, 2017, the entirety of which areincorporated by reference herein.

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates to a lens driving mechanism, and more particularlyto a lens driving mechanism that can move lenses using electromagneticforce.

Description of the Related Art

In existing dual-lens camera systems, two lens driving modules areusually arranged close to each other, and as a result, magneticinterference between the magnets of the two lens driving modules islikely to occur, causing the focus speed and accuracy of the lenses tobe adversely affected. Therefore, what is needed is a dual-lens camerasystem that can prevent magnetic interference between the two lensdriving modules.

BRIEF SUMMARY OF THE INVENTION

In view of the aforementioned problems, an object of the invention is toprovide a lens driving mechanism that can reduce the magneticinterference generated by the magnetic elements of the lens drivingmodules, thereby improving the focus speed and accuracy of the lenses inthe camera system.

An embodiment of the invention provides a lens driving mechanism fordriving a first lens and a second lens to move, wherein light enters thefirst and second lenses along a light incident direction. The lensdriving mechanism includes a first base movably connected to the firstlens, a first driving assembly, and a second driving assembly. The firstdriving assembly has a first magnet and a first coil correspondingthereto for moving the first lens. The second driving assembly has asecond magnet and a second coil corresponding thereto for moving thesecond lens. The first magnet is adjacent to the second magnet, and thepolar direction of the first magnet is parallel to the light incidentdirection.

In some embodiments, the lens driving mechanism further includes amagnetic permeable element connected to the first magnet.

In some embodiments, the magnetic permeable element is disposed on aside of the first magnet, and the first magnet is located between themagnetic permeable element and the first coil.

In some embodiments, the polar direction of the second magnet isperpendicular to the light incident direction.

In some embodiments, the first magnet comprises a multipolar magnethaving a first magnetic portion and a second magnetic portion, and thepolar directions of the first and second portions are opposite to eachother and parallel to the light incident direction.

In some embodiments, the height of the second magnet along the lightincident direction is greater than the height of the first magnet alongthe light incident direction.

In some embodiments, the polar direction of the second magnet isparallel to the light incident direction.

In some embodiments, the first and second magnets respectively comprisea multipolar magnet, and the polar directions of the first and secondmagnets are parallel to the light incident direction.

In some embodiments, the first coil is disposed on the first base,corresponding to the first magnet to move the first lens relative to thefirst base along a horizontal direction, wherein the horizontaldirection is perpendicular to the light incident direction.

In some embodiments, the lens driving mechanism further includes asecond base, and the second coil is disposed on the second base andcorresponds to the second magnet, to move the second lens relative tothe second base.

In some embodiments, the lens driving mechanism further includes a lensholder with the first lens received therein, a frame connected to thefirst base, a magnetic field sensor disposed on an outer side of thelens holder, and a magnetic element disposed on the frame, wherein themagnetic field sensor measures the magnetic field strength of themagnetic element to learn the position offset of the first lens holderrelative to the first base.

In some embodiments, the lens driving mechanism further includes aconductive circuit formed on the lens holder by insert molding, LaserDirect Structuring, or Molded Interconnect Devices technology, whereinthe first coil is a planar coil disposed on the lens holder andelectrically connected to the conductive circuit.

In some embodiments, the lens holder has a substantially rectangularstructure, and the magnetic field sensor is disposed at a corner of thelens holder.

In some embodiments, the lens holder has a substantially rectangularstructure, and the magnetic field sensor and the magnetic element aredisposed on a side of the lens holder, corresponding to the firstmagnet.

In some embodiments, the lens driving mechanism further includes amagnetic permeable element connected to the first magnet and situatedbetween the magnetic element and the first magnet.

In some embodiments, the lens driving mechanism further includes a lensholder with the first lens received therein, a frame connected to thefirst base, a reference magnet affixed to the frame, and a magneticfield sensor disposed on an outer side of the lens holder and above thefirst coil, wherein the first coil magnetically cooperate with thereference magnet to move the lens holder relative to the frame along thelight incident direction, and the magnetic field sensor measures themagnetic field strength of the reference magnetic to learn the positionoffset of the first lens relative to the first base.

In order to illustrate the purposes, features, and advantages of theinvention, the preferred embodiments and drawings of the invention areshown in detail as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be more fully understood by reading the subsequentdetailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1 is a schematic view of a lens driving mechanism in accordancewith an embodiment of the invention;

FIG. 2 is an exploded view of the lens driving module in FIG. 1;

FIG. 3 is a cross-sectional view taken along line A-A′ in FIG. 1;

FIG. 4 is a partial enlarged view of the lens driving mechanism in FIG.3;

FIG. 5 is a partial cross-sectional view of a lens driving mechanism inaccordance with another embodiment of the invention;

FIG. 6 is a partial cross-sectional view of a lens driving mechanism inaccordance with another embodiment of the invention;

FIG. 7 is a partial cross-sectional view of a lens driving mechanism inaccordance with another embodiment of the invention;

FIG. 8 is a partial cross-sectional view of a lens driving mechanism inaccordance with another embodiment of the invention;

FIG. 9 is a partial cross-sectional view of a lens driving mechanism inaccordance with another embodiment of the invention;

FIG. 10A is a schematic view showing relative positions of the magnetsand coils of a lens driving module in accordance with another embodimentof the invention; and

FIGS. 10B to 10D are schematic views showing relative positions of thelens holder, magnets, coils, and two set of magnetic element andmagnetic field sensor of a lens driving module in accordance withanother embodiment of the invention.

FIG. 10E is a schematic views showing relative positions of the lensholder, magnets, coils, and a set of magnetic element and magnetic fieldsensor of a lens driving module in accordance with another embodiment ofthe invention.

FIG. 10F is a schematic views showing relative positions of the lensholder, magnets, coils, and a set of magnetic element and magnetic fieldsensor of a lens driving module in accordance with another embodiment ofthe invention.

FIG. 10G is a schematic views showing relative positions of the lensholder, magnets, coils, and a magnetic field sensor of a lens drivingmodule in accordance with another embodiment of the invention.

FIG. 11 is a schematic view showing relative positions of the magnetsand coils of a lens driving mechanism in accordance with anotherembodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The making and using of the embodiments of a lens driving mechanism arediscussed in detail below. It should be appreciated, however, that theembodiments provide many applicable inventive concepts that can beembodied in a wide variety of specific contexts. The specificembodiments discussed are merely illustrative of specific ways to makeand use the embodiments, and do not limit the scope of the disclosure.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. It should be appreciated thateach term, which is defined in a commonly used dictionary, should beinterpreted as having a meaning conforming to the relative skills andthe background or the context of the present disclosure, and should notbe interpreted in an idealized or overly formal manner unless definedotherwise.

Referring to FIGS. 1-3, FIG. 1 is a perspective diagram of a lensdriving mechanism 1 according to an embodiment of the invention, FIG. 2is an exploded diagram of a lens driving module 2 of the lens drivingmechanism 1 in FIG. 1, and FIG. 3 is a sectional view along line A-A′ inFIG. 1. In this embodiment, two lens driving modules 2 of the lensdriving mechanism 1 may comprise Voice Coil Motors (VCMs) which arearranged along a longitudinal direction (the X axis) and may be disposedin a handheld electronic device, such as mobile phone or tabletcomputer. The two lens driving modules 2 may have the same specificationand are capable of Optical Image Stabilization (OIS) and Auto focusing(AF), but the invention is not limited thereto.

As shown in FIGS. 1-3, each of the lens driving modules 20 primarilycomprises a top casing 10, a base 20, a lens holder 30, a coil 40, aframe 50, four magnets 60, an upper spring sheet 70, a lower springsheet 72, a plurality of flexible members 74, a circuit board 80, adriving board 90, and two magnetic sensors 92.

The top casing 10 has a hollow structure and is affixed to the base 20.It should be noted that the top casing 10, the base 20, and the lensholder 30 respectively form holes 12, 22, and 32, wherein an opticallens is secured in the hole 32 of the lens holder 30. Light can enterthe lens driving module 2 via the hole 12 along the optical axis O ofthe lens (the light incident direction) and propagate sequentiallythrough the lens and the hole 22 to an image sensor (not shown) belowthe base 20.

The coil 40 is wound around the outer peripheral surface of the lensholder 30, and the four magnets 60 are affixed to four sides of theframe 50, corresponding to the coils 40.

In this embodiment, the lens holder 30 and the lens therein aresuspended in the center of the frame 50. More specifically, the lensholder 30 is movably connected to the frame 50 by the upper spring 70and the lower spring 72 made of a metal material. When current issupplied to the coil 40, the coil 40 can act with the magnetic field ofthe magnets 60 to generate a magnetic force to move the lens holder 30and the lens along the Z axis with respect to the frame 50. In someembodiments, the four magnets 60 may include at least one bipolar ormultipolar magnet, and the polar directions (N-S) of some of the magnets60 may be perpendicular to the Z axis. Specifically, as shown in FIG. 4,the polar directions (N-S) of the two adjacent magnets 60 respectivelyin the two lens driving modules 2 may be parallel to the Z axis.

One end of the four suspension wires 74 is affixed to the circuit board80 and the other end is connected to the upper spring 70, so that theframe 50, the lens holder 30 and the lens therein can move relative tothe base 20 along a horizontal direction. In some embodiments, thesuspension wires 74 may comprise a metal material.

The circuit board 80, such as a flexible printed circuit board (FPC), isaffixed to the base 20 and electrically connected to the driving board90. In this embodiment, the circuit board 80 not only transmitselectrical signals to the driving board 90, but also transmitselectrical signals to the coils 40 through the suspension wires 74 andthe upper spring 70, thereby performing the AF and OIS functions.

In this embodiment, two magnetic field sensing elements 92 arerespectively mounted on two sides of the base 20. The two magnetic fieldsensing elements 92 may be Hall effect sensors, MR sensors, or Fluxgatesensors, and can be used to learn the position offset amount of theframe 50 and the lens holder 30 with respect to the base 20 in the X andY directions.

As shown in FIGS. 3 and 4, because the two lens driving modules 2 in thelens driving mechanism 1 are close to each other, magnetic interferencebetween two adjacent magnets 60 respectively in the two lens drivingmodules 2 is likely to occur, causing the focus speed and accuracy ofthe lenses to be adversely affected. To address the aforementionedproblem, the polar directions (N-S) of the two adjacent magnets 60(first and second magnets) respectively in the lens driving modules 2are both parallel to the Z axis (FIG. 4). Thus, adverse influence to thefocus speed and accuracy of the lenses (first and second lenses) in thelens driving modules 2 due to magnetic interference therebetween can beefficiently prevented.

In the left lens driving module 2 of FIG. 4, one of the magnets 60(first magnets) can cooperate with the coil 40 or the coils disposed inthe driving board 90 to constitute a first driving assembly. Morespecifically, the magnet 60 can magnetically cooperate with the coil 40(first coil) to generate a magnetic force, so that the lens holder 30and the lens (first lens) in the left lens driving module 2 can be movedrelative to the base 20 (first base) along the Z axis to perform the AFfunction. Additionally, the magnet 60 in the left lens driving module 2can also magnetically cooperate with the driving board 90 (first coil)to generate a magnetic force, so that the frame 50, the lens holder 30,and the lens (first lens) in the left lens driving module 2 can be movedtogether relative to the base 20 (first base) along a horizontaldirection to perform the OIS function.

Similarly, in the right lens driving module 2 of FIG. 4, one of themagnets 60 (second magnets) can cooperate with the coil 40 or the coilsdisposed in the driving board 90 to constitute a second drivingassembly. More specifically, the magnet 60 can magnetically cooperatewith the coil 40 (second coil) to generate a magnetic force, so that thelens holder 30 and the lens (second lens) in the right lens drivingmodule 2 can be moved relative to the base 20 (second base) along the Zaxis to perform the AF function. Additionally, the magnet 60 in theright lens driving module 2 can also magnetically cooperate with thedriving board 90 (second coil) to generate a magnetic force, so that theframe 50, the lens holder 30, and the lens (second lens) in the rightlens driving module 2 can be moved together relative to the base 20(second base) along a horizontal direction to perform the OIS function.

Referring to FIG. 5, in another embodiment of the lens driving mechanism1, two magnetic permeable elements 62 are respectively disposed on thetwo adjacent magnets 60 of the adjacent lens driving modules 2, so as tofurther suppress magnetic interference between the two lens drivingmodules 2. As shown in FIG. 5, the magnets 60 are located between themagnetic permeable elements 62 and the driving boards 90, respectively.Referring to FIG. 6, in another embodiment of the lens driving mechanism1, a magnetic permeable element 62 is disposed on the top side of theleft magnet 60 (first magnet) which has a polar direction (N-S) parallelto the Z axis. More specifically, the magnetic permeable element 62 hasa flat structure extending in a direction perpendicular to the polardirection (N-S) of the left magnet 60. On the other hand, the magnet 60(second magnet) in the right lens driving modules 2 has a polardirection (N-S) perpendicular to the Z axis. Since the polar directions(N-S) of the two adjacent magnets 60 are different, magneticinterference between the two lens driving modules 2 can be suppressed.

Referring to FIG. 7, in another embodiment of the lens driving mechanism1, the magnet 60 (first magnet) in the left lens driving module 2comprises a multipolar magnet, such as a quadrapolar magnet. In someembodiments, the magnet 60 may also be constituted by two or moremagnetic elements. Since the magnet 60 in the left lens driving module 2can be magnetized along a vertical direction, it has a polar direction(N-S) parallel to the Z axis. When compared with the vertical direction(the Z axis), the magnet 60 in the left lens driving module 2 canprovide a lower magnetic field intensity in the horizontal direction, sothat magnetic interference between the two lens driving modules 2 alongthe horizontal direction can be suppressed. Specifically, as shown inFIG. 7, the magnet 60 (first magnet) in the left lens driving module 2primarily has a first magnetic portion 611 on the left side and a secondmagnetic portion 612 on the right side, wherein the polar directions(N-S) of the first and second magnetic portions 611 and 612 are oppositeto each other and parallel to the Z axis.

Referring to FIG. 8, the two adjacent magnets 60 (first and secondmagnets) respectively in the two lens driving modules 2 are bothmultipolar magnets. Since the polar directions (N-S) of the first andsecond magnetic portions 611 and 612 in the two magnets 60 are bothparallel to the Z axis, the magnetic interference between the two lensdriving modules 2 can be suppressed, and the focus speed and accuracy ofthe lenses can therefore be improved.

Referring to FIG. 9, another embodiment of the magnet 60 (first magnet)in the left lens driving module 2 has a polar direction (N-S) parallelto the Z axis with a magnetic permeable element 62 disposed thereon,however, the polar direction (N-S) of the magnet 60 (second magnet) inthe right lens driving module 2 is perpendicular to the Z axis.Specifically, the height of the right magnet 60 (second magnet) alongthe Z axis is greater than the height of the left magnet 60 (firstmagnet) along the Z axis. Since the magnetic permeable element 62 cansuppress magnetic interference between the two magnets 60, and the leftand right magnets 60 (first and second magnets) have different polardirections (N-S), the magnetic interference between the two lens drivingmodules 2 can be efficiently suppressed.

It should be noted that the annular coil 40 wound on the lens holder 30of the left lens driving module 2 as shown in FIG. 2 is omitted in FIG.9 because the magnet 60 (first magnet) in the left lens driving module 2is mainly used to magnetically cooperate with the coil (first coil) inthe driving board 90, whereby the frame 50, the lens holder 30 and thelens (first lens) can be moved relative to the base 20 along thehorizontal direction to perform the OIS function. However, the AFfunction can still be achieved by other magnets 60 and coils which aredisposed in the left lens driving module 2.

In an exemplary embodiment, an arrangement of coils and magnets of FIG.10A can be applied to either one of the two lens driving modules 2. Asshown in FIG. 10A, two pairs of magnets 60 can be arranged in either oneof the lens driving modules 2, wherein the magnets 60 may be multipolarmagnets corresponding to four coils C1 in the driving board 90 belowthem, so that the coils C1 can magnetically cooperate with the magnets60 to produce magnetic forces and perform the OIS function.

Additionally, two oval coils C2 are disposed on opposite sides of thelens holder 30, corresponding to a pair of magnets 60. Since the ovalcoils C2 can magnetically cooperate with the magnets 60 to producemagnetic forces and perform the AF function, the large coil 40 shown inFIG. 2 is no longer needed. The other pair of magnets 60 are providedwith magnetic permeable elements 62 and can magnetically cooperate withthe coils C1, so as to produce magnetic forces and perform the OISfunction. As the large coil 40 in FIG. 2 can be omitted in the presentembodiment by using the oval coils C2, the dimensions of the lensdriving module 2 along the X axis can be efficiently reduced, andminiaturization of the lens driving mechanism 1 can be achieved. In someembodiments, the widths of the coils C1 and C2 may exceed the widths ofthe magnets 60, so that the electromagnetic forces produced by themagnets 60 and the coils C1, C2 can be increased, and the performance ofthe lens driving mechanism 1 can therefore be improved.

FIGS. 10B to 10D show relative positions of the lens holder, magnets,coils and magnetic field sensors of a lens driving module in accordancewith another embodiment of the invention. In this embodiment, at least aconductive circuit 301 is formed on the lens holder 30 by insertmolding, Laser Direct Structuring (LDS) or Molded Interconnect Devices(MID). Two magnetic field sensors S1 and S2 are disposed on an outersurface of the lens holder 30 and electrically connected to theconductive circuit 301. Accordingly, two magnetic elements M1 such aspermanent magnets are affixed to the frame 50 (FIG. 2). While the lensholder 30 and the lens therein move relative to the frame 50 along the Zaxis, the two magnetic field sensors S1 and S2 can measure the magneticfield strengths of the magnetic elements M1 and M2, so as to learn theposition offset of the lens holder 30 and the lens (first lens) thereinwith respect to the frame 50 and the base 20 (first base) in the Zdirection.

As shown in FIGS. 10B to 10D, the magnetic field sensor S1 and themagnetic element M1 are close to each other and located at a corner ofthe lens holder 30. The magnetic field sensor S2 and the magneticelement M2 are close to each other and located on a side of thesubstantially rectangular lens holder 30, wherein the magnetic elementM2 is located above one of the magnetic permeable elements 62 (FIG.10C). That is, the magnetic permeable element 62 is situated between themagnetic element M2 and the magnet 60 (first magnet) below the magneticpermeable element 62, so that magnetic interference between the magneticelement M2 and the magnet 60 can be suppressed.

The two coils C2 (first coils) in FIGS. 10B to 10D may be oval or planarcoils embedded in a substrate which is disposed on an outer surface ofthe lens holder 30, and they can magnetically cooperate with thecorresponding magnets 60 to perform the AF function. It should be notedthat the coils C2 are also electrically connected to conductive circuit301 and communicated with the magnetic field sensing elements S1 and S2through a controller, so that a closed-loop control for the AF functioncan be achieved. In an exemplary embodiment, the two magnetic fieldsensing elements S1 and S2 may be Hall effect sensors, MR sensors, orFluxgate sensors.

Referring to FIG. 10E, in this embodiment, only the magnetic fieldsensor S1 and the magnetic element M1 are provided in the lens drivingmodule to learn the position offset amount of the lens holder 30 withrespect to the frame 50 in the Z direction, wherein the magnetic fieldsensor S1 and the magnetic element M1 are arranged at a corner of thelens holder 30. In another embodiment, as shown in FIG. 10F, only themagnetic field sensor S2 and the magnetic element M2 are provided in thelens driving module to learn the position offset amount of the lensholder 30 with respect to the frame 50 in the Z direction, wherein themagnetic field sensor S2 and the magnetic element M2 are arranged on aside of the substantially rectangular lens holder 30, corresponding toone of the magnets 60 below the magnetic permeable element 62.

Referring to FIG. 10G, another embodiment of the magnetic field sensorS2 can also be disposed on an outer side of the lens holder 30 andlocated above one of the coils C2 (first coils). The coil C2 (firstcoil) below the magnetic field sensor S2 can magnetically cooperate withthe corresponding magnet 60 (reference magnet) which is affixed to theframe 50 and close to the magnetic field sensor S2, so as to move thelens holder 30 relative to the frame along the Z axis. Additionally, themagnetic field sensor S2 can measure the magnetic field strength of themagnet 60 (reference magnet), to learn the position offset amount of thelens holder 30 with respect to the frame 50 in the Z direction. In theconfiguration of FIG. 10G, since the magnetic field sensor S2 candirectly measure the magnetic field strength of the magnet 60 (referencemagnet) to learn the position offset amount of the lens holder 30, themagnetic element M2 in FIG. 10F is no longer needed, so that the spacefor other components in the lens driving module can be increased, toachieve miniaturization of the lens driving mechanism.

FIG. 11 shows relative positions of magnets and coils of a lens drivingmechanism 1 in accordance with another embodiment of the invention. Forthe sake of simplicity and clarity, the lens holder 30, the coils 40,and the frame 50 are not presented in FIG. 11. As shown in FIG. 11, thedriving board 90 in the right lens driving module 2 is disposed abovethe base 20 (second base), and the coils C1 (second coils) disposed inthe driving board 90 can electromagnetically act with the magnets 60(second magnets), whereby the frame 50, the lens holder 30, and the lens(second lens) received in the lens holder 30 can be moved along thehorizontal direction to perform the OIS function. In some embodiments,the bases 20 (first and second bases) of the two lens driving modules 2can be integrally formed in one piece.

Still referring to FIG. 11, the left lens driving module 2 has amultipolar magnet 60 (first magnet) adjacent to the right lens drivingmodule 2, and a magnetic permeable element 62 is disposed on themultipolar magnet 60. Specifically, the height h1 of the magnet 60(second magnet) in the right lens driving module 2 is greater than theheight h2 of the magnet 60 (first magnet) in the left lens drivingmodule 2. Thus, the electromagnetic force between the two lens drivingmodules 2 can be reduced, and the space for other components in the leftlens driving module 2 can be increased, to achieve high performance andminiaturization of the lens driving mechanism 1.

Although embodiments of the present disclosure and their advantages havebeen described in detail, it should be understood that various changes,substitutions and alterations can be made herein without departing fromthe spirit and scope of the disclosure as defined by the appendedclaims. For example, it will be readily understood by those skilled inthe art that many of the features, functions, processes, and materialsdescribed herein may be varied while remaining within the scope of thepresent disclosure. Moreover, the scope of the present application isnot intended to be limited to the particular embodiments of the process,machine, manufacture, composition of matter, means, methods and stepsdescribed in the specification. As one of ordinary skill in the art willreadily appreciate from the disclosure of the present disclosure,processes, machines, manufacture, compositions of matter, means,methods, or steps, presently existing or later to be developed, thatperform substantially the same function or achieve substantially thesame result as the corresponding embodiments described herein may beutilized according to the present disclosure. Accordingly, the appendedclaims are intended to include within their scope such processes,machines, manufacture, compositions of matter, means, methods, or steps.In addition, each claim constitutes a separate embodiment, and thecombination of various claims and embodiments are within the scope ofthe disclosure.

What is claimed is:
 1. A lens driving mechanism for driving a first lensand a second lens to move, wherein light enters the first and secondlenses along a light incident direction, the lens driving mechanismcomprising: a first base, movably connected to the first lens; a firstdriving assembly, having a first magnet and a first coil correspondingto the first magnet for moving the first lens; and a second drivingassembly, having a second magnet and a second coil corresponding to thesecond magnet for moving the second lens, wherein the first magnet isadjacent to the second magnet, and the polar direction of the firstmagnet is parallel to the light incident direction.
 2. The lens drivingmechanism as claimed in claim 1, further comprising a magnetic permeableelement connected to the first magnet.
 3. The lens driving mechanism asclaimed in claim 2, wherein the magnetic permeable element is disposedon a side of the first magnet, and the first magnet is located betweenthe magnetic permeable element and the first coil.
 4. The lens drivingmechanism as claimed in claim 1, wherein the polar direction of thesecond magnet is perpendicular to the light incident direction.
 5. Thelens driving mechanism as claimed in claim 4, further comprising amagnetic permeable element connected to the first magnet.
 6. The lensdriving mechanism as claimed in claim 5, wherein the magnetic permeableelement is disposed on a side of the first magnet, and the first magnetis located between the magnetic permeable element and the first coil. 7.The lens driving mechanism as claimed in claim 1, wherein the firstmagnet comprises a multipolar magnet having a first magnetic portion anda second magnetic portion, and the polar directions of the first andsecond portions are opposite to each other and parallel to the lightincident direction.
 8. The lens driving mechanism as claimed in claim 7,further comprising a magnetic permeable element connected to the firstmagnet.
 9. The lens driving mechanism as claimed in claim 8, wherein themagnetic permeable element is disposed on a side of the first magnet,and the first magnet is located between the magnetic permeable elementand the first coil.
 10. The lens driving mechanism as claimed in claim1, wherein the height of the second magnet along the light incidentdirection is greater than the height of the first magnet along the lightincident direction.
 11. The lens driving mechanism as claimed in claim1, wherein the polar direction of the second magnet is parallel to thelight incident direction.
 12. The lens driving mechanism as claimed inclaim 1, wherein the first and second magnets respectively comprise amultipolar magnet, and the polar directions of the first and secondmagnets are parallel to the light incident direction.
 13. The lensdriving mechanism as claimed in claim 1, wherein the first coil isdisposed on the first base, corresponding to the first magnet to movethe first lens relative to the first base along a horizontal direction,wherein the horizontal direction is perpendicular to the light incidentdirection.
 14. The lens driving mechanism as claimed in claim 1, furthercomprising a lens holder with the first lens received therein, a frameconnected to the first base, a magnetic field sensor disposed on anouter side of the lens holder, and a magnetic element disposed on theframe, wherein the magnetic field sensor measures the magnetic fieldstrength of the magnetic element to learn the position offset of thefirst lens holder relative to the first base.
 15. The lens drivingmechanism as claimed in claim 1, further comprising a second base,wherein the second coil is disposed on the second base and correspondsto the second magnet, to move the second lens relative to the secondbase.
 16. The lens driving mechanism as claimed in claim 14, furthercomprising a conductive circuit formed on the lens holder by insertmolding, Laser Direct Structuring, or Molded Interconnect Devicestechnology, wherein the first coil is a planar coil disposed on the lensholder and electrically connected to the conductive circuit.
 17. Thelens driving mechanism as claimed in claim 14, wherein the lens holderhas a substantially rectangular structure, and the magnetic field sensoris disposed at a corner of the lens holder.
 18. The lens drivingmechanism as claimed in claim 14, wherein the lens holder has asubstantially rectangular structure, and the magnetic field sensor andthe magnetic element are disposed on a side of the lens holder,corresponding to the first magnet.
 19. The lens driving mechanism asclaimed in claim 18, further comprising a magnetic permeable elementconnected to the first magnet and situated between the magnetic elementand the first magnet.
 20. The lens driving mechanism as claimed in claim1, further comprising a lens holder with the first lens receivedtherein, a frame connected to the first base, a reference magnet affixedto the frame, and a magnetic field sensor disposed on an outer side ofthe lens holder and above the first coil, wherein the first coilmagnetically cooperate with the reference magnet to move the lens holderrelative to the frame along the light incident direction, and themagnetic field sensor measures the magnetic field strength of thereference magnetic to learn the position offset of the first lensrelative to the first base.